HDDR -
if your kids have to get up or make noise it isn't really noticeable -
but at the Luau - you had to be quiet so you could actually hear what they were saying - and it was really distracting when people were walking around.
HDDR is a must do for us every trip. Our kids absolutely love it and belly laugh at the whole show. On our last trip a few weeks ago, they had their 4th trip to HDDR and they laughed harder than ever and we are still talking about some of the jokes at home. Their favorite is "My Darling Clementine"
HDDR is first choice, but with kids the age of yours, Backyard BBQ wouldn't be a bad choice. Lots of singing and dancing with the characters. We didn't like it much, but mostly because our older ones had no interest in it.
We took our boys who were 9 and 11 (at the time) to both the Luao and the HDDR. They enjoyed both but the HDDR was the highlight of our dining experiences with them. They still talk about it 6 years later!!